1. Technical Field
The present invention relates to a method of producing an organic EL device.
2. Related Art
An organic EL (electroluminescent) device includes a light emitting element in which a light emitting layer (functional layer) formed of an organic light emitting material is situated between an anode (pixel electrode) and a cathode (counter electrode). In the organic EL device, the light emitting layer, the cathode, a cathode protective layer, an organic buffer layer, and a gas barrier layer are stacked in this order from the side of the substrate, for example.
As described in JP-A-2007-69548, for example, a screen printer is used to produce the organic buffer layer. The method of producing the organic EL device includes disposing a screen mesh above the cathode protective layer disposed over the substrate, printing (transferring) a printing material in a pattern by using a squeegee, and removing the screen mesh.
The organic buffer layer preferably has a smaller thickness to reduce the overall thickness of the organic EL device for improving luminance. However, a portion of a printer or a transfer apparatus (a screen mesh of a screen printer, for example) may come in contact with the cathode protective layer during the formation of such an organic buffer layer having a small thickness. The contact may cause damage such as the formation of a crack to the cathode protective layer, and a component of the organic buffer layer (epoxy resin, for example) may enter the cathode protective layer through the crack. This may lead to deterioration of the cathode positioned below the cathode protective layer. As a result, the organic EL device may have a non-light-emitting area.